[Ffmpeg-devel-irc] ffmpeg.log.20180308

burek burek021 at gmail.com
Fri Mar 9 03:05:01 EET 2018


[00:22:18 CET] <Aison> ffprobe shows me: Unsupported codec with id 100359 for input stream 1
[00:22:27 CET] <Aison> what is this codec 100359?
[00:24:47 CET] <DHE> dunno. it's unknown.
[00:25:41 CET] <Aison> I guess one of these streams is bad? https://nopaste.xyz/?2ccfff252de6c4c3#tQPUCr/n6Hs8tEJIT36KN0Y4hkE91+idUgPTckugGnQ=
[01:43:10 CET] <chocolaterobot> kepstin: ` ffmpeg -framerate 6 -loop 1 -i image.png -i audio.ogg -c:v libx264 -preset veryfast -c:a copy -shortest -pix_fmt yuv420p  output.mkv` still results in the same upload error message on youtube
[01:57:21 CET] <chocolaterobot> can anyoen help?
[04:19:56 CET] <hendry> how would you describe the difference between 2560x1440 and 3840x2160? 2560x1440 2/3 of the size of 4k?
[04:26:07 CET] <klaxa> 1440p is to 2560p what 720p is to 1080p
[04:58:22 CET] <kepstin> hendry: 1440p is sometimes called "2.5K" :/
[05:07:06 CET] <ubercow> it took me an embarrassingly long time to realize 1440p and 2.5k were the same thing
[05:22:22 CET] <hendry> klaxa, kepstin thanks guys
[09:10:09 CET] <kinglox> Hi, i have problem that i cant find answer on internet, i tried to read ffmpeg documentation but with no success, i have video and audio files that i want to stream to rtmp, so i wound like python program that loads video in opencv, and loads audio file, and then stream that to ffmpeg, but i dont have success
[09:11:03 CET] <kinglox> I am coding on linux, i also read about named pipes, but problem is how will ffmpeg sync video and audio
[09:11:44 CET] <kinglox> can somebody help with it, with some idea :)
[09:12:27 CET] <pmjdebruijn> are you getting audio+video seperately?
[09:13:22 CET] <kinglox> yes, n different files, problem is that i want to dynamicly change videos and audios files
[09:14:15 CET] <kinglox> currently i manage to stream raw frame by frame to ffmpeg, but i dont know how to stream audio to it too
[09:17:14 CET] <kinglox> @pmjdebruijn command = ['ffmpeg','-y','-f','rawvideo','-s', dimension,'-re','-pix_fmt', f_format,'-i', '-','-f','alsa','-i','hw:2,1','-vcodec','libx264','-pix_fmt','yuv420p','-b:v','3000k','video4.avi']
[09:17:54 CET] <kinglox> this is my current command, i tried to stream music to virtual device and that input it like that to ffmpeg
[09:18:14 CET] <kinglox> i open ffmpeg command as subprocces in python
[09:19:28 CET] <kinglox> but it didn't worked maybe because i failed somewhere, but does someone have some recommendation
[10:20:56 CET] <fps> DHE: hmm, AVCodecContext has no field codecpar, at least not according to the docs
[10:21:27 CET] <DHE> fps: what version of ffmpeg though? codecpar is probably a ~3.2 edition, maybe later
[10:23:52 CET] <fps> AVStream does have a field codecpar.. https://ffmpeg.org/doxygen/3.4/structAVCodecContext.html
[10:24:04 CET] <fps> AVCodecContext seems to share many fields with AVCodecParameters though
[10:25:30 CET] <fps> oh, there's avcodec_parameters_from_context()
[10:25:32 CET] <fps> hmm
[10:28:22 CET] <fps> that's not helping either.. hmm.
[10:28:52 CET] <fps> soo, let's start at the beginning.. an AVCodec represents the codec itself (in my case i'm using libx264), right?
[10:29:44 CET] <fps> an AVCodecContext on the other hand is like a parametrization of a particular instance of a codec? I.e. it's what's used in the end to actually encode stuff, right?
[10:34:23 CET] <fps> the initialization of the codec context is already "interesting". 1] look up the codec, 2] allocate a codec context passing in the codec found in step 1. 3] set some wanted fields in the context and 4] call avcodec_open2 (who came up with these names) to further initializa the codec context given the codec and, i guess, values from step 3
[10:36:35 CET] <fps> DHE: oops, avcodec_parameters_from_context() DID help.  i was changing my original source, but not the test case.. doh :)
[10:38:28 CET] <DHE> AVCodecContext is the parameter passed to an actual encoder/decoder. codecpar is all the information about a video/audio stream anyone would need to know short of actually encoding/decoding it
[10:39:14 CET] <DHE> it's enough to tell you it's 1920x1080 H264 or whatever, which is enough for the container. it mainly needs to fill in the fields in the file indicating what the codec is, etc.
[10:40:56 CET] <fps> yeah, that makes sense..
[12:26:15 CET] <Cyb3rn3t> hi all!
[12:26:52 CET] <Cyb3rn3t> I have performance issues with ffmpeg 3.4,
[12:27:14 CET] <Cyb3rn3t> however the 3.3 is much faster in encoding with nvenc
[12:27:29 CET] <Cyb3rn3t> did somebody noticed the same ?
[12:30:46 CET] <DHE> interesting. can you reproduce with two ffmpeg binaries? (asking to make sure nvidia drivers are not involved)
[12:31:45 CET] <DHE> and make sure it's the same input, etc.
[17:11:23 CET] <jya> oh can I make ffplay call libswresample so that this file https://raw.githubusercontent.com/jyavenard/htmltests/master/mediatest/mp4/ChID-BLITS-EBU-4.mp4 plays properly on mac?
[17:11:28 CET] <jya> s/oh/how
[17:11:43 CET] <jya> when I play it on mac, all channels but left and right are dropped
[21:06:22 CET] <leif> I seem to have found many different (conflicting) ways to allocate an AVBuffer. Is there a canonical way that libraries should allocate an AVBuffer?
[21:09:59 CET] <leif> There also seems to be two different AVBuffer types in ffmpeg. I'm looking for one that I can use for logging.
[21:28:53 CET] <leif> AH! Theres a difference between AVBuffer and AVBPrintf...
[21:29:32 CET] <leif> AVBprint*
[21:32:46 CET] <xzcvczx> is there a way to make ./configure print to stdout and not be silent?
[21:33:37 CET] <durandal_1707> it prints at end, otherwise very hard to do it print all the time
[21:34:10 CET] <c_14> xzcvczx: if you want to see what it's doing just tail -f config.log
[21:34:59 CET] <xzcvczx> yeah thats what i am doing but it seems to just stop doing anything with the last 2 things in config.log being "mktemp -u XXXXXX\n<random string>"
[21:38:02 CET] <xzcvczx> is that a known issue and/or is there a workaround for it?
[21:45:30 CET] <HD|Laptop> Hello everyone
[21:46:24 CET] <HD|Laptop> I am trying to follow https://trac.ffmpeg.org/wiki/Capture/Webcam on OS X 10.11.6, using ffmpeg version 3.4 from MacPorts
[21:46:56 CET] <HD|Laptop> With ffmpeg -f avfoundation -list_devices true -i "" I can see my FaceTime camera and my HDMI screencaster as sources just fine
[21:47:24 CET] <HD|Laptop> but when I try capturing, e.g. with ffmpeg -f avfoundation  -video_device_index 0 -audio_device_index 1 -video_size 1920x1080 out.mp4, I get "[NULL @ 0x7f844b019800] Requested output format 'avfoundation' is not a suitable output format\nout.mp4: Invalid argument"
[21:48:27 CET] <HD|Laptop> (same for using -i 1 and leaving the other options at the end away)
[21:50:36 CET] <alexp> what if you type -c:a aac before the out.mp4 ?
[21:51:02 CET] <alexpigment> i wonder if it's just that it's trying to choose mp4 but the audio format is like PCM and the container won't accept it
[21:51:42 CET] <alexpigment> either way, you'll notice that all the examples use out.mpg
[21:51:45 CET] <alexpigment> there may be a reason for that
[21:53:44 CET] <HD|Laptop> tried with -c:a aac, with additionally -c:v libx264, and all combos with mp4, mov, mpg
[21:53:47 CET] <HD|Laptop> always same error
[21:54:11 CET] <alexpigment> does it seem weird to you that it says nout.mp4 ?
[21:54:12 CET] <HD|Laptop> https://pastebin.com/s3BNEsUR
[21:54:17 CET] <HD|Laptop> heres the full text
[21:54:28 CET] <alexpigment> oh, newline ;)
[21:54:30 CET] <BtbN> you're just not ever specifying any input device with -i
[21:54:32 CET] <HD|Laptop> @alexpigment, the \n was from me, as I cannot paste multiline ;)
[21:54:43 CET] <BtbN> so it takes all your options as output options for your mp4
[21:54:47 CET] <HD|Laptop> argh
[21:55:26 CET] <HD|Laptop> [avfoundation @ 0x7f8f09008800] Selected framerate (29.970030) is not supported by the device
[21:55:41 CET] <HD|Laptop> so for fullhd it offers [avfoundation @ 0x7f8f09008800]   1920x1080@[60.000240 60.000240]fps [avfoundation @ 0x7f8f09008800]   1920x1080@[30.000030 30.000030]fps
[21:55:50 CET] <HD|Laptop> thats some weird framerates
[21:56:15 CET] <alexpigment> yeah those are new to me
[21:58:25 CET] <HD|Laptop> @alexpigment, neither -framerate 30 or -r 30 seem to help, it always looks for that weird 29.97fps
[21:58:44 CET] <HD|Laptop> I also tried using the webcam as video source, it offers me [avfoundation @ 0x7f91f300fa00]   1280x720@[1.000000 30.000000]fps
[21:58:53 CET] <HD|Laptop> that sounds cleaner but still the same error
[22:00:27 CET] <alexpigment> are you forcing the frame rate?
[22:01:47 CET] <HD|Laptop> aaah now it works. apparently one has to put -framerate before -i
[22:04:18 CET] <kepstin> yes, in general options in ffmpeg go before the thing they affect. input options go before a specific input, output options before a specific output
[22:04:31 CET] <kepstin> (you can have multiple inputs and outputs in one command, so it can get complex)
[22:06:09 CET] <HD|Laptop> there is only one thing left, there is no audio
[22:06:14 CET] <xzcvczx> c_14: ah ok figured it out, apples current version of "as" doesn't like random crap being thrown at it in probe_cc for figuring out the version
[22:06:31 CET] <HD|Laptop> is there a way I can take the avfoundation audio only and pass it right to the system speakers using ffmpeg?
[00:00:00 CET] --- Fri Mar  9 2018


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